Run the tuning parts in an add-on version

Hello, I make cars in add-on version. But I do not know how to add the tunning parts on the add-on version. I was told it was in the carcols but not more. If someone could help me and tell me what to add in the carcols

If you are trying to convert a "replace car" to addon, and the author have tuning parts to it, just search the <kits> to </kits> section in carcols.meta of the replace car and rename each part model as per required by the add-on car's name.